For the transport of fluids that includes both liquids and gases, it is desirable to form a fluid-tight sealed connection when jointing two or more pipe sections together. Numerous applications exist for transporting drain or storm, potable, or waste water using pipe sections fabricated from thermoplastic materials such as polyethylene, polypropylene, polyvinyl chloride (PVC), high density polyethylene (HDPE), and the like.
One common pipe configuration for the transport of fluids includes dual-wall corrugated piping, having a smooth interior wall, optimizing fluid flow characteristics and a corrugated outer wall for enhanced strength and durability. Connecting the dual wall corrugated pipe sections is generally achieved by installing an oversized end of a first corrugated pipe section referred to as a bell over a spigot located at the end of a second corrugated pipe section. Seated in the one of the many corrugated sections or annular grooves of the spigot's outer diameter is typically a gasket that assists in forming a fluid-tight seal between the pipe sections. One example of a gasket design for such application, as well as for other purposes includes U.S. Pat. No. 7,469,905 that issued Dec. 30, 2008 and assigned to SpringSeal, Inc. (Streetsboro, Ohio) entitled PERMANENTLY LUBRICATED FILM GASKET AND METHOD OF MANUFACTURE (hereinafter “the '905 patent”), which is incorporated herein by reference in its entirety. The elastomeric gasket contacts each of the pipe sections to form a sealed connection assembly between the pipe sections.
Typically, a large frictional force is encountered when the spigot and the gasket are inserted into the bell of the outer pipe section. As one end of the inner pipe is pushed into the enlarged end or bell of the outer pipe section's pipe connector, the gasket is at times, undesirably pulled from the groove by the large frictional force. When the pipe is not properly sealed, ground water may leak into the pipe or fluid may leak out of the pipe and contaminate the ground or area surrounding the pipe sections.
It is not uncommon for the joining sections of the corrugated pipe to be exposed to numerous forces causing stress to the gasket over the life of the connection. Such stress may allow the gasket to move from its desired location or allow debris to infiltrate the gasket seat, reducing the effectiveness of the sealing assembly connection.